Torrential rains in eastern Africa have raised the Nile River to its highest level in 20 years. The river is about to burst its banks in Sudan's capital, Khartoum.

Low-lying sections of Khartoum have already been flooded. In some districts of the city, people have been climbing onto dikes to escape the rising floodwaters.

An official with the Red Crescent Society, Siegfried Soler, says he is shocked at how fast the Nile is rising. "Flooding occurs regularly along the Nile River," he said. "But this year it has come early and we have been amazed at how fast the water levels are rising. The International Federation has launched an appeal to support ongoing relief work."

Areas outside the capital have also been severely affected by the flooding. Whole villages are under water, and tens of thousands of people have been forced to flee their homes to escape the floodwaters.

According to Mr. Soler, people, having lost their crops and livestock, are surviving on emergency aid. "More than 20,000 have been forced to move from their homes in the states of River Nile and Sinnar, in north Sudan," he said. "And at least another 16,000 are threatened by it. At the moment we have around 200 volunteers from the Sudanese Red Crescent distributing food, blankets, and providing first aid and social support in several of the affected areas."

Aid workers say they are especially concerned about providing for about two million internally displaced people who live in shantytowns around Khartoum.

And the worst is probably to come. The floods are not expected to peak until next week.